if c and d are integers, is c even
1. c(d+1) is even
2. (c+2) (c+4) is even
gmat prep question
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- Prasanna
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Is the answer B.yvonne12 wrote:if c and d are integers, is c even
1. c(d+1) is even
2. (c+2) (c+4) is even
(1) c(d+1) is even. This could be the case when c and d is even or when c and d is odd. Hence not sufficient
(2) (c+2)(c+4) is even. This means c should be even. Hence sufficient.
- jayhawk2001
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Agree with C. (Though my first guess was also B )
1. Clearly INSUFF as explained by Prasanna.
2. This stmt guarantees that C is even in all the cases except when C = 0; this statement is true but it doesn't tells about C (because 0 is neither even nor odd)- so INSUFF.
But if we combine both, first statement tells that C is not zero. (because something multiplied by C is even).
Therefore C.
1. Clearly INSUFF as explained by Prasanna.
2. This stmt guarantees that C is even in all the cases except when C = 0; this statement is true but it doesn't tells about C (because 0 is neither even nor odd)- so INSUFF.
But if we combine both, first statement tells that C is not zero. (because something multiplied by C is even).
Therefore C.
- jayhawk2001
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Hmm, OG quants (Green book) tells us that the sequence -4, -2, 0, 2, 4 ...mendiratta wrote:Agree with C. (Though my first guess was also B )
1. Clearly INSUFF as explained by Prasanna.
2. This stmt guarantees that C is even in all the cases except when C = 0; this statement is true but it doesn't tells about C (because 0 is neither even nor odd)- so INSUFF.
But if we combine both, first statement tells that C is not zero. (because something multiplied by C is even).
Therefore C.
is even.
I just checked wikipedia and it says 0 is even as well.
https://en.wikipedia.org/wiki/Even_and_odd_numbers
Not sure how it can be C, given the above...